Empty Pathgrid record is considered as the modder's intention to delete any existing record.

apps/opencs/CMakeLists.txt

@@ -19,7 +19,7 @@ opencs_hdrs_noqt (model/doc
 
 opencs_units (model/world
     idtable idtableproxymodel regionmap data commanddispatcher idtablebase resourcetable nestedtableproxymodel idtree infotableproxymodel landtexturetableproxymodel
-    actoradapter
+    actoradapter idcollection
     )
 
 

apps/opencs/model/world/idcollection.cpp

@@ -0,0 +1,43 @@
+#include "idcollection.hpp"
+
+namespace CSMWorld
+{
+    template<>
+    int IdCollection<Pathgrid, IdAccessor<Pathgrid> >::load (ESM::ESMReader& reader, bool base)
+    {
+        Pathgrid record;
+        bool isDeleted = false;
+
+        loadRecord (record, reader, isDeleted);
+
+        std::string id = IdAccessor<Pathgrid>().getId (record);
+        int index = this->searchId (id);
+
+        if (record.mPoints.empty() || record.mEdges.empty())
+            isDeleted = true;
+
+        if (isDeleted)
+        {
+            if (index==-1)
+            {
+                // deleting a record that does not exist
+                // ignore it for now
+                /// \todo report the problem to the user
+                return -1;
+            }
+
+            if (base)
+            {
+                this->removeRows (index, 1);
+                return -1;
+            }
+
+            std::unique_ptr<Record<Pathgrid> > baseRecord(new Record<Pathgrid>(this->getRecord(index)));
+            baseRecord->mState = RecordBase::State_Deleted;
+            this->setRecord(index, std::move(baseRecord));
+            return index;
+        }
+
+        return load (record, base, index);
+    }
+}

apps/opencs/model/world/idcollection.hpp

@@ -5,6 +5,7 @@
 
 #include "collection.hpp"
 #include "land.hpp"
+#include "pathgrid.hpp"
 
 namespace CSMWorld
 {
@@ -153,6 +154,9 @@ namespace CSMWorld
 
         return true;
     }
+
+    template<>
+    int IdCollection<Pathgrid, IdAccessor<Pathgrid> >::load(ESM::ESMReader& reader, bool base);
 }
 
 #endif

apps/opencs/model/world/pathgrid.hpp

@@ -20,7 +20,7 @@ namespace CSMWorld
     {
         std::string mId;
 
-        void load (ESM::ESMReader &esm, bool &isDeleted, const IdCollection<Cell>& cells);
+        void load (ESM::ESMReader &esm, bool &isDeleted, const IdCollection<Cell, IdAccessor<Cell> >& cells);
         void load (ESM::ESMReader &esm, bool &isDeleted);
     };
 }